Ink for textile marking



Patented Dec. 30, 1941 INK FOR TEXTILE MARKING Francis M. Sell, Cincinnati, Ohio, assignor to The National Marking Machine Company, Cincinnati, Ohio, a corporation of Ohio No Drawing. Application May 20, 1937,

I Serial No. 143,853

21 Claims.

The object of my invention is to provide an ink for textile marking, by the use of which the marked textiles may be subjected to ordinary laundering or cleaning operations or the like, and

thereafter the marks will be (when exposed to ordinary lighting) substantially invisible on all colors and types of textiles and may be rendered clearly visible upon the application of rays of suitable wave length or characteristics, particularly a substance which exhibits fluorescence under ultra-violet ray illumination.

This application is in part a continuation of my co-pending application Serial No. 17,334, filed April 19, 1935.

In practice I have demonstrated that my object maybe attained by using as the fluorescent ingredient a substantially colorless fluorescent dyestuff, which may be defined as follows ical compound which is substantially colorless (viewed under normal light), highly fluorescent (viewed under ultra-violet rays and in the substantial absence of normal light), and which has the property of being irreversibly transferred from a solution to a textile to which it is applied.

The term colorless fluorescent dyestufi will be used in that sense hereinafter, in the specification and claims. A "colorless fluorescent dyestuil', may also be defined as a compound which is substantive to textile fibers and which on the fibers is substantially invisible under normal light but fluorescent under filtered ultra-violet rays. More technically I may describe this compound as having either no chromophoric groups, or weak chromophoric groups, strong fluorophoric groups and strong auxochromic groups.

To accomplish, my object it is essential that this dyestufi remain substantially colorless and fluorescent and that it still adhere to the textile to which it has been applied after that textile has been subjected to an ordinary laundering 'or cleaning operation or the like.

In the present invention, I employ as the marking ink, a colorless fluorescent dyestuii dissolved in a vehicle. The dyestufi is one that when the ink is printed on the fabric (or otherwise marked thereupon) is colorless when viewed under normal light, but which is strongly fluorescent under ultra violet rays. It is noted that a dyestuff is a substance which when applied in solution to a textile material, becomes irreversibly attached to said textile material, and theterm is so used A chem-' herein. The dyestufis used in the present invention are such as do not, when printed on the textile fabricieither before or after laundering or cleaning the fabric) give a color, when viewed under ordinary light, but which do exhibit a substantially completely removable from the textile fabric by an ordinary laundering or cleaning operation to which the textile article is subjected.

One of the dyestuffs which I have used commercially for this purpose has the following structure:

S 03H S 0311 O H H H H E sage-N acpmom This compound may be classed as stilbene dyestufl. This is substantive to cotton.

Another dyestuff that may be used' for this purpose has the following structure:

This compound may be classed as a thiazole dyestuff. This is substantive to both cotton and wool and silk.

This example is continued from my copending application Ser. No. 17,334 filed April 19, 1935, wherein this particular dyestuff was described as useful for the purpose here employed.

Another dyestuif' that may be used for this purpose has the following structure:

This compound may be classed as a coumarine dyestuii. This is substantive to silk and wool.

Another dyestufi that may be used for this purpose has the following structure:

(CHshN a)2 This compound may be classed as a phenylethylene dyestufi'. This is substantive to wool ing the ink is one that will be completely or 69 and i The general subject of dyestuffs is known to chemists, and the general subject of fluorescence is also known to physicists and to chemists. Obviously, chemists skilled in this art may com--v pound various ingredients which will accomplish the same results as those herein specifically mentioned. Hence, I wish to be understood as not limiting my invention to the specific structure of the dyestuffs mentioned.

It is well known to chemists that certain dyestuffs are substantive to vegetable fibers, such as linen and cotton, and other dyestufis are substantive to animal fibers, such as silk and wool. There are few dyes, relatively speaking, that are substantive to both vegetable and animal fibers. In order to accomplish my object it is obvious that I may (and preferably do) use two or more of the above mentioned dyestuffs. The reason for this is the fact that laundries usually (or at least frequently) receive, in a parcel of articles to be laundered, several difierent kinds of articles, made of different kinds of fabrics, e. g. silk or woolen articles and cotton or rayon articles. It is desirable (and from a practical and commercial standpoint essential) that the one stamping ink should be capable of effective use on all the common kinds of fabrics to be encountered, in ordinary goods to be laundered.

In preparing my new ink I dissolve any selected one or more of said dyestuffs in a vewith a laundry marking machine it may be transferred from an inking pad to type in the ordi-- nary manner, and then transferred from the type to the textile to be marked in the ordinary man ner. It is also necessary that this vehicle must have such a degree of surface tension that when applied to a textile it will not excessively bleed and thereby become illegible. Furthermore, it must have a drying rate such that when used, for instance, on a laundry marking machine, it may be transferred from an inking pad to the type and from the type to the textile before undue evaporation. Furthermore, this vehicle must be of such characteristics that when the ink in which the vehicle is used is applied to a textile,

' The vehicle of the ink is thus seen to be comthe ordinary laundering process.

posed essentially of materials that are substantially completely removable from the fabric by Some of the liquid components of the ink'are preferably less volatile than water.

I have produced commercially successful ink as follows: 20 gms. of dyestuif, such as the hereinbefore mentioned stilbene dyestufi, are dissolved in 400 cos. of glycerine, and 100 cc. of iso propyl alcohol and 500 cc. of ethylene glycol mono butyl ether are added and stirred.

Another ink which I have demonstrated as practical is as follows: 20 gms. of dyestuif, such as the hereinbefore mentioned thiazole dyestuff, are dissolved in 500 ccs. of triethylene glycol and 500 ccs. of diethylene glycol mono methyl ether are added.

Another ink which I have demonstrated as practical is as follows: 20 gms. of dyestuff, such as the hereinbefore mentioned coumarine dyestuif, are dissolved in 200 cos. of glycerine and 200 cos. of iso propyl alcohol, 100 ccs. of triethanolamine, and 500 ccs. of ethylene glycol mono ethyl ether are added.

Another ink which I have demonstrated as practical is as follows: 20 gms. of dyestuff, such as the hereinbefore mentioned phenylethylene dyestuff, are dissolved in 200 cos. of glycerine and 200 ccs. of oleic acid, 100 ccs. of iso propyl alcohol and 500 ccs. of ethylene glycol mono butyl dyestuff to dye the textile.

By dye I mean the irreversible transferring of the dyestuff from the solution to the textile. This is the common usage of the verb dye.

I have found in practice that the presence of a small amount, at least, of an abnormal liquid, such as water, glycerine,'glycols, or the like, causes the vehicle of the ink to act as a dye bath. For certain of my dyestuffs the addition of a weak acid, such as oleic acid, or a weak base, such as triethanolamine, causes the ink to have improved dyeing properties. Such weak acids and bases do not injure the fabric or any colored dye already carried thereon. In this connection I note that many of the articles commonly sent not to modify the colors of the articles, in any manner.

Certain of the ingredients that can safelybe used in the vehicle of my new inks are: glycerine,

ethylene glycol, triethylene glycol, iso propyl alcohol, propyl alcohol, ethylene glycol mono butyl ene glycol mono methyl ether, sulfonated castor oil, oleic acid, triethanolamine, and pine oil.

- ether, ethylene glycol mono ethyl ether, diethylether are added.

The above examples must be considered as representative of a large number of possible types of inks, and I do not wish to be understood as limiting my invention to the specific formulae herein disclosed.

For the purpose of enabling an operator to readily and easily read the identification marks in the textiles after the textiles have been subjected to the laundering or dry cleaning operations, and all normally visible portions of the marks thereby removed, I have commercially successfully accomplished this in the following manner: The textiles are placed in a dimly lighted room and subjected to rays of such wave length or characteristics that when applied to the mark they will cause the fluorescent ingredient remaining in the textile to become brilliantly fluorescent, to the extent that the mark may be clearly seen at a considerable distance. In practice, I have demonstrated that these rays may be obtained by the use of an ultra violet lamp. I have also found that with filtered ultra violet rays substantially .all ingredients having this flucrescent character may be energized to become brilliantly fluorescent. I preferably employ the filtered .ultravioletrays because of economy in operation and because they are harmless to the operators. It will of course be obvious that any ultra-violet ray lamp to be used should be one which does not, when in use, give any considerable amount of white light. It is for that reason that I have mentioned filtering the ultra-violet rays, by which means I allow the ultra-violet rays to impinge upon the laundry marks without any considerable amount of light. I,use the expression in the substantial absence of light in the claims to indicate the absence of more light than would normally be present in a dimly lighted room; I have also demonstrated that so-called X-rays and cathode rays will cause certain fluorescent ingredientsunderthe same conditions to become brilliantly fluorescent, but X-ray and cathode rays will not thus excite as many different kinds of fluorescent compounds as will the ultra violet rays. In view of the foregoing I desire to be understood as including in my invention the use of rays having properties, equivalent for my purpose, to those of ultra violet rays. V

In certain of the appended claims I have in- V eluded laundering and dry-cleaning, in the generic expression a cleaning operation, which expression is intended to be substantially equivalent to a laundering or dry-cleaning operation.

My new ink as covered in the present application, is now being commercially used in numerous laundries throughout the United States and principal foreign countries, and it is the general practice to use it as follows: When usedon a laundry marking machine a small quantity of the ink'is poured upon the inking pad. Then the textile to be marked is placed upon the platen and the marking machine operated to press the type first upon the pad and then upon the textile. When this has been done a large portion of the ink is deposited upon the surface of the article, but a suflicient quantity is pressed into or absorbed bythe fibers so that after the textile is subjected to a laundering or cleaning operation and the surface ink all or partly removed, there will remain enough of the fluorescent ingredient to define the mark thus printed. After the laundering or cleaning operation the textile is subjected to the action of the ultra violet rays and the mark caused to become brilliantly fluorescent and clearly visible to the operator.

' Heretofore, with the use of indelible colored ink for laundry marking purposes it was the custom to employ type of smallest possible size and to place the mark in concealed, relatively inaccessible portions of the textile. This was for the purpose of making the laundry marks inconspicuous on the laundered articles. With my improved ink it is now the common practice to employ type of relatively large size and to place the mark in conspicuous and readily accessible portions of the textiles, for instance upon the outer upper surface of folded handkerchiefs. Hence, in assorting the articles into customers bundles much time is saved and so-called shorts and longs in a laundry are substantially eliminated. Furtherstiffness in said fabric after such cleaning operation.

2 An ink for textile identification marking which comprises a vehicle and a colorless fluorescent organic dyestuff in solution therein, said tification characters upon fabrics, such dyestuffs stantial absence of light, although invisible unmore, much of an operator's time is saved in the marking operation because the operator does not need to hunt for a concealed or inaccessible portion of the textile.

Laundries and dry cleaning establishments which are now using my new ink have entirely eliminated the great objection to their work caused by the presence of black identification marks on all laundry articles, and in addition have efiected a substantial economy in the operation of the marking and redistributing departments.

I claim as my invention:

1. An ink for textile identification marking which comprises a vehicle and a plurality of substantially colorless flourescent organic dyestuflfs dissolved therein, said dyestuffs being invisible on any fabric to which they are applied, when viewed under ordinary light, but visibleon said fabric when viewed under utlra-violet rays in the substantial absence of light, and said dyestuffs including at least one that is substantive to cellulosic fibres and at least one that is substantive to animal fibres, the vehicle of such ink being sufliciently removable in ordinary cleaningder ordinary light, after said fabrics have undergone a laundering operation, and said vehicle being substantially entirely removable by an ordinary laundering operation.

4.- An ink for textile identification marking, which comprises a colorless fluorescent organic dyestuif capable of exhibiting fluorescence when printed upon a textile material and when exposed to ultra-violet rays, and a vehicle therefor, said ink being of a consistency capable of being printed by type upon a textile material, said dyestufi when so applied to textiles, resisting ordinary laundering operations and resisting drycleaning operations, and being thereafter clearly visible and legible when exposed to ultra-violet rays in the substantial absence of light, said vehicle being substantially wholly removable from said textile materials by an ordinary laundering operation and by an ordinary dry-cleaning operation. l

5. An ink for textile identification marking which comprises a plurality of substantially colorless fluorescent organic dyestuffs and a viscous liquid vehicle therefor, one at least of said dyestuffs being a silk and wool dye and one at least of said dyestufis being a cotton dye, said dyestuiTs being fast to ordinary laundering, and said liquid vehicle being substantially removable by an ordinary laundering, and said ink being of a consistency suitable for being applied to a fabric by means of type, each of said dyestuffs when printed upon a, textile product to which said dyestuff is substantive, being substantially invisible under ordinary light but being visibly fluorescent when subjected to ultra-violet rays in a semidark room.

6. An ink for textile identification marking, comprising a substantially colorless fluorescent organic dyestufi which is fluorescent under ultraviolet ray s, dissolved in a vehicle, said vehicle comprising glycerine, iso-propyl alcohol and ethylene glycol mono butyl ether, in the following proportions:

said dyestuff when on a fabric, being fast to an ordinary launderingoperation and thereafter being substantially invisible under ordinary light..

but clearly visible under ultra-violet rays, the vehicle of such ink being sufficiently removable in ordinary cleaning operations to produce sub- "stantially no increase in stiffness in said fabric ations to produce substantially no increase in stiffness in said fabric after such cleaning operation.

8. An ink suitable for textile identification marking which is a viscousliquid vehicle carrying a substantially colorless fluorescent dyestuif having its structural formula selected from the group consisting of which dyestuif, applied to fabricsis fast to ordinary laundering and leaves on the laundered fabric, a mark which is not visible under ordinary light, but clearly visible under ultra-violet rays in the substantial absence of light, and said liquid vehicle being substantially completely removable by ordinary laundering.

9. An ink suitable for textile identification marking which is a viscous liquid vehicle carrying a substantially colorless fluorescent dyestuff having the structural formula SOsH O H H O mNO x tat MG, 7

.S 0311 S 03H which dyestuif, applied to fabrics is fast to ordinary laundering 8nd leaves on the laundered fabric a mark which is not visible under ordinary light, but clearly visible under ultra-violet rays in a semi-dark room, and said liquid vehiing a substantially colorless fluorescent dyestufi having the structural formula which dyestuif, applied to fabrics is fast to ordinary laundering and leaves on the laundered fabric a mark which is not visible under ordinary light, but clearly visible under ultra-violet rays in the substantial absence of light, and said liquid vehicle being substantially completely removable by ordinary laundering.

' 11. An ink suitable for textile identification marking which is a viscous liquid vehicle carrying a substantially colorless fluorescent dyestuff I having the structural formula 1330 o w H which dyestufi, applied to fabrics is fast to ordinary laundering and leaves on the laundered fabric a mark which is not visible under ordinary light, but clearly visible under ultra-violet rays, and said liquid vehicle being substantially completely removable by ordinary laundering.

12. An ink suitable for textile identification which comprises a viscous solution, in a liquid vehicle of a substantially colorless fluorescent cathode rays, in the substantial absence of light.

13. An ink suitable for textile identification which comprises a viscous solution, in a liquid vehicle of a substantially colorless fluorescent stilbene dyestuif, which dyestuif'when applied upon a textile fabric article, is fast to ordinary laundering, and said vehicle being substantially completely removable by ordinary laundering, said dyestuff when printed upon the textile product, being substantially invisible under ordinary light, but being visibly fluorescent when subjected to radiations selected from the group consisting of ultra-violet rays, X-rays and cathode rays, in the substantial absence of light.

14.An ink suitable for textile identification which comprises a viscous solution, in a liquid vehicle of a substantially colorless fluorescent thiazole dyestuif, which dyestufi, applied upon a textile fabric, is fast to ordinary laundering, and said vehicle being substantially completely removable by ordinary laundering, said dyestufl when printed upon the textile product, being substantially invisible under ordinary light, but

being visibly fluorescent when subjected to radiations selected from the group consisting of ultra-violet rays, X-rays and cathode rays, in

- the substantial absence of light.

15. An ink suitable for textile identification which comprises a viscous solution, in a liquid vehicle of a substantially colorless fluorescent coumarine dyestufi, which dyestuif, applied upon a textile material, is fastto ordinary laundering, and said vehicle being substantially completely removable by ordinary laundering, said dyestuff when printed upon the textile product, being substantially invisible under ordinary light, but being visibly fluorescent when subjected to radiations selected from the group consisting of ultraviolet rays, X-rays andcathode rays, in the substantial absence of light.

16. An ink suitable for textile identification which comprises a water-soluble viscous liquidsolvent that is less volatile'than water, containing in solution therein, a substantially colorless fluorescent dyestuif selected from the group consuitable for identifying ownership of the same,

such mark consisting of a dyeing with a colorless fluorescent organic dyestuii which, on the textile is fast to an ordinary laundering process and is fast toan ordinary dry-cleaning process, and the said identifying mark being invisible under ordinary light but clearly visibleunder ultra-violet rays in the substantial absence oflight, and the marked area being indistinguishable from the remainder of the fabric except by the said fluorescence which is clearly visible under ultra-violet rays in the substantial absence of light.

18. Textile fabric articles carrying fluorescent identifying marks thereupon, suitable for identifying ownership of the same, such mark consisting of a dyeing with the para-hydroxy compound of dehydro-thio-p-tcluidine which, on the textile articles is fast to an ordinary laundering process and is fast to an ordinary dry-cleaning process. and the said identifying mark being invisible under ordinary light but clearly visible under ultra-violet rays in the substantial absence of light, and the marked area being indistinguishable from the remainder of the fabric of said articles except. by the said fluorescence which is clearly visible under ultra-violet rays in the substantial absence of light. a

19. An article of manufacture Willing a fabric of a character requiring a launderingoporation, an identification mark thereon in the form of specific legible characters, which mark is substantially invisible when viewed under ordinary light, and composed of a vehicle of a sticky and viscous substance upon the surface of and penetrated into and around the fibers of the fabric and being of a character substantially wholly removable in a laundering operation, and a colorless organic dyestuil mixed with said vehicle and fixed in the manner of a dye to the fibers of the fabric in the same patterns as that of the vehicle, said dyestuif being one that is fluorescent under ultra-violet rays in the substantial absence of light, but invisible in normal light, and being fast to laundering, when on said fabric.

20. An improvementin the art of fabric article identification marking, which comprises the step of dyeing upon a completely manufactured textile fabric article, an identifying mark comprising characters legible by exposure to ultra violet rays in the substantial absence of light, and said characters being made with a composition which contains an organic dyestuil carried in a vehicle, said dyestufi being colorless'under ordinary light, and the dyestufi when applied on said fabric article being substantially fast to laundering and to dry cleaning operations, and showing fluorescence when'subiected to ultraviolet rays in the substantial absence of light, and said vehicle being composedessentially of material which is substantially completely removable from said fabric article during an ordinary cleaning operation, the said marking being left legible on the fabric article by ultraviolet rays in the substantial absence of light, after said cleaning step, whereby on the cleaned article the identification mark is left invisible under ordinary light while remaining visible under ultraviolet rays in the substantial absence of light.

21. An improvement in the art of fabric article identification marking, which comprises the step of dyeing upon a completely manufactured textile fabric article, an identifying mark comprising distinctive characters legible by exposure to ultra-violet rays in the substantial absence of light, said characters being madewith a composition which consists essentially of a dyestuif carried in a vehicle, said dyestufi' being colorless under ordinary light and including at least one colorless dyestuif selected from the group consisting of a stilbene dyestuif, a thiazcle dyestufl', a coumarine dyestufi and a phenylethylene dyestuff, and the dyestufi when so applied on said fabric article being sufliciently fast to laundering and dry cleaning operations and showing fluorescence when subjected to ultra-violet rays in the substantial absence of light, and said vehicle being composed essentially of material which is substantially completely removable from said fabric article during ordinary cleaning operations, the said marking being left legible by ultra-violet rays in the substantial absence of light, on the fabric article after said cleaning step.

' more M. sum 

